An airplane is controlled in 3 axis while in flight. the 3 axis are roll, pitch, and yaw.
Roll axis is the wing tips moving up and down...the ailerons control the roll axis.....the ailerons are at the back of the wing and move opposite of each other...left one up and right down and vise a versa.....ailerons are controlled by the side to side movement of the right stick......move the stick right and the right aileron goes up when you're looking from the back of the plane forward....
pitch axis is the nose of the airplane moving up and down....pitch axis is controlled by the elevators...the elevators are at the back of the horizontal stab.(the little wing at the back of the plane) they move together both up or both down. The elevators are contolled by the fore and aft movement of the right stick
Yaw axis is the nose of the plane moving left or right....the rudder controls the yaw axis...the rudder is at the back of the vertical stab and moves left or right with the side to side movement of the left stick....
Now that is the very basics......and I won't go further to keep from confusing you....
To turn you probably won't need rudder you can use just ailerons....but if you do use rudder you'll probably have to reduce aileron throw or actually use opposite of rudder to keep from rollong over.....
Sims are a good tool...but there is no substitute for stick time....have you gone to your local RC club yet?